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1.
Curr Microbiol ; 80(9): 290, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37462776

RESUMO

Grow-out and hatchery units of shrimps are being impacted by disease-causing bacterial pathogens and predominantly marine Vibrios. The use of chemicals for governing bacterial pathogens in the aquaculture practices is developing resistance to bacteria. Henceforth, the application of bio-therapeutic agents from marine resources for controlling pathogens is most vital to be considered. Molecular docking is computer-assisted drug design tool to detect and counteract for drug-receptor interaction for known target protein of diseases. Therefore, an effort was made with the extract of the marine micro alga Skeletonema costatum against hemolysin protein of pathogenic bacteria Vibrio harveyi. The extract of S. costatum was tested against growth and virulence produced by V. harveyi during larviculture of Penaeus monodon. The extract was analyzed for phyto-constituents through GC-MS and used them as ligand molecule in docking. S. costatum extract at 200 µg mL-1 was found to decrease 35.20% of cumulative percentage mortality (CPM) in postlarvae of P. monodon against V. harveyi infections. The biomolecule Docasane, an alkane from the extract of S. costatum, exposed highest binding interaction than other compounds during docking analysis. The level of significance (P < 0.05) was found in CPM, growth, and virulence factors of V. harveyi studies. Thus, the present finding predicts that extract of S. costatum containing biomolecules can be recommended for use in the shrimp culture-based grow-out and hatchery units for eliminating bioluminescent V. harveyi.


Assuntos
Microalgas , Vibrio , Proteínas Hemolisinas , Simulação de Acoplamento Molecular
2.
BMC Public Health ; 23(1): 2217, 2023 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-37950181

RESUMO

BACKGROUND: Vaccine hesitancy is a complex phenomenon that threatens global health. Present-day communication technology has paved the way for self-education but also contributed to the infodemic surrounding vaccination. This has resulted in pockets of people who are reluctant, refuse recommended vaccinations, or choose to delay being vaccinated. The present study was designed to estimate the magnitude of hesitancy towards the COVID-19 vaccination and determine its associated factors in the community. METHODS: This cross-sectional study was conducted among 776 adults aged ≥ 18 years in 15 clusters in Puducherry district, India, between March 2022 and May 2022. Face-to-face interviews were conducted using a validated, structured questionnaire. Socio-demographic variables, co-morbidities, attitudes towards vaccination, etc., were expressed as frequencies and percentages. Vaccine hesitancy was dichotomized with the median score as the cut-off and reported as a proportion with a 95% confidence interval. Univariate and multivariate analyses were carried out to determine the factors associated with vaccine hesitancy. RESULTS: The mean age of participants was 43.3 ± 14.8 years, with the majority being female (67.0%). Nearly 92.4%, 74.4%, and 0.5% of participants received their first, second, and precautionary doses, respectively, during the study period. Among the unvaccinated, 93.2% were unwilling to receive any dose of vaccination. More than half of the participants were hesitant towards vaccination, according to the vaccine hesitancy scale. Participants aged above 45 years were less hesitant, while those educated up to school level, belonging to the upper socio-economic class, never tested for COVID-19 in the past, and having a negative attitude towards vaccination were significantly associated with higher vaccine hesitancy. CONCLUSIONS: It is imperative to address vaccine hesitancy by alleviating existing fears and misconceptions in the community through efficient communication strategies to win the fight against current as well as future public health emergencies.


Assuntos
COVID-19 , Humanos , Adulto , Feminino , Pessoa de Meia-Idade , Masculino , COVID-19/epidemiologia , COVID-19/prevenção & controle , Estudos Transversais , Vacinas contra COVID-19 , Índia/epidemiologia , Comunicação , Vacinação
3.
Arch Microbiol ; 203(7): 4243-4258, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34097104

RESUMO

Shrimp grow-out and hatchery systems are being affected by bacterial disease particularly Vibrios. The use of chemotherapeutic agents in aquaculture practices has to lead to the development of resistance among aquatic bacteria. Thus, health management becomes of major importance in aquaculture. Under this situation, progressing bio-inhibitors from marine resources are most appropriate to be considered against pathogenic bacteria. Molecular docking is an appropriate tool in structural biology and computer-assisted drug design to predict and neutralize a target protein of known diseases. In this study, marine macro-alga Ulva fasciata was aimed at developing inhibitors against luminescence disease-causing pathogenic bacteria Vibrio harveyi. U. fasciata was collected from Thoothukudi, Tamil Nadu, India. Extract of U. fasciata was tested against growth and virulence factors of V. harveyi during Penaeus monodon larviculture. Further U. fasciata extract was subjected to GC-MS analysis to identify the biomolecules. The homology modeling of virulent protein, hemolysin of V. harveyi was designed in this study. Hence, it was aimed for molecular docking against the biomolecules identified from U. fasciata extract. During shrimp larviculture, the extract of U. fasciata (200 µg mL-1) exhibited reduction on Cumulative Percentage of Mortality (32.40%) in postlarvae against challenge of V. harveyi infection. Biomolecule Methyl dehydroabietate had showed highest binding affinity among the compounds was evaluated in molecular docking study. Statistical analysis had revealed significant differences (p < 0.05) in trials. Therefore, it was proved that the bio-inhibitors from U. fasciata will be a better option for controlling luminescence disease-causing V. harveyi in shrimp grow-out practices.


Assuntos
Proteínas Hemolisinas , Simulação de Acoplamento Molecular , Extratos Vegetais , Ulva , Vibrio , Animais , Proteínas Hemolisinas/química , Proteínas Hemolisinas/metabolismo , Índia , Penaeidae/microbiologia , Extratos Vegetais/farmacologia , Ulva/química , Vibrio/efeitos dos fármacos , Vibrio/fisiologia
4.
Ophthalmology ; 124(3): 295-302, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28065436

RESUMO

PURPOSE: To objectively assess the long-term posterior capsule opacification (PCO) and neodymium-doped yttrium aluminium garnet (Nd:YAG) capsulotomy rate of a square-edge (SE) polymethylmethacrylate (PMMA) intraocular lens (IOL) modification in comparison with a round-edge (RE) PMMA IOL or an SE hydrophobic acrylic IOL (SE-Acrylic). DESIGN: Prospective, randomized, controlled fellow eye clinical study. PARTICIPANTS: Ninety-four patients scheduled for bilateral phacoemulsification had an SE-PMMA IOL implanted in 1 eye. An RE-PMMA IOL was implanted in the fellow eye in 46 patients (group A), and an SE-Acrylic IOL was implanted in the fellow eye in 48 patients (group B). Randomization was used to determine group assignment and which IOL was implanted in the first eye to undergo surgery. METHODS: Evaluation of Posterior Capsule Opacification (EPCO) image analysis software was used to objectively grade PCO density from standardized, high-resolution retroillumination photographs obtained annually for the first 5 postoperative years and at year 9. MAIN OUTCOME MEASURES: The PCO scores and Nd:YAG capsulotomy rate. RESULTS: Nine-year follow-up was achieved by 72% from group A and 63% from group B. In group A, the mean PCO score was significantly lower in the SE-PMMA IOL eyes compared with the contralateral RE-PMMA eyes at all follow-up visits (P < 0.05). In group B, the mean PCO score was statistically lower in the SE-PMMA IOL eyes compared with the contralateral SE-Acrylic IOL eyes at all but the 1- and 3-year follow-up visits. Nine-year Nd:YAG capsulotomy rates were 2% for SE-PMMA IOLs versus 37% for RE-PMMA IOLs in group A (P < 0.001), and 4% for SE-PMMA IOLs versus 10% for SE-Acrylic IOLs in group B (P = 0.435). The RE-PMMA PCO rate did not plateau and continued to increase throughout the 9-year study period. CONCLUSIONS: This prospective, 9-year fellow eye comparison study suggests that an inexpensive PMMA IOL design modification-a squared optic edge-could significantly reduce the burden of vision-impairing secondary membrane in developing countries.


Assuntos
Opacificação da Cápsula/prevenção & controle , Implante de Lente Intraocular , Lentes Intraoculares , Facoemulsificação , Polimetil Metacrilato , Cápsula Posterior do Cristalino , Resinas Acrílicas , Adulto , Idoso , Feminino , Seguimentos , Humanos , Lasers de Estado Sólido , Masculino , Pessoa de Meia-Idade , Capsulotomia Posterior/estatística & dados numéricos , Estudos Prospectivos , Desenho de Prótese , Método Simples-Cego , Acuidade Visual/fisiologia
6.
Am J Trop Med Hyg ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38955199

RESUMO

Given India's goal of eliminating malaria by 2030, this study aimed to investigate community perspectives on malaria in highly endemic areas of Odisha, a region historically prone to malaria. The research explores self-reported malaria events, community knowledge, attitudes, practices, health-seeking behaviors, and access to healthcare services. A community-based cross-sectional survey conducted among 387 households between November 2022 and May 2023 served as an extension of our recent project, monitoring malaria elimination efforts in remote and challenging-to-reach communities in Odisha. The participants, who had a mean (SD) age of 41.7 (13.17) years, were predominantly male (88.4%). Self-reported malaria in the last 12 months prior to the survey was 6.2%, with half of the patients opting for primary health centers for treatment, averaging a 5-day recovery per episode. The median cost per malaria treatment episode was U.S. dollars 20.17. A significant majority (79.8%) demonstrated a strong awareness of malaria symptoms and transmission, with 83.3% expressing a favorable attitude toward disease prevention. Notably, 65.1% reported consistent use of long-lasting insecticidal nets. However, nearly half of the participants reported inadequate larval source management and indoor residual spraying services. Although there were slight variations in knowledge, attitude, and practice scores among demographic groups, the overall understanding of and approach to malaria were consistent in the study population, with no statistically significant differences (P >0.05). The study findings offer hope, suggesting that with sustained dedication and focused surveillance, malaria could become a thing of the past.

7.
Artigo em Inglês | MEDLINE | ID: mdl-23295480

RESUMO

Europium is shown to be a good anomalous scatterer in SAD phasing for solving the structure of biological macromolecules. The large value of the anomalous contribution of europium, f'' = 11.17 e(-), at the Cu Kα wavelength is an advantage in de novo phasing and automated model building. Tetragonal crystals of hen egg-white lysozyme (HEWL) incorporating europium(III) chloride (50 mM) were obtained which diffracted to a resolution of 2.3 Šat a wavelength of 1.54 Š(Cu Kα). The master data set (360° frames) was split and analyzed for anomalous signal-to-noise ratio, multiplicity, completeness, SAD phasing and automated building. The structure solution and model building of the split data sets were carried out using phenix.autosol and phenix.autobuild. The contributions of the Eu ions to SAD phasing using in-house data collection are discussed. This study revealed successful lysozyme phasing by SAD using laboratory-source data involving Eu ions, which are mainly coordinated by the side chains of Asn46, Asp52 and Asp101 together with some water molecules.


Assuntos
Cristalografia por Raios X/métodos , Európio/metabolismo , Muramidase/química , Muramidase/metabolismo , Sítios de Ligação , Európio/química , Modelos Moleculares , Conformação Proteica , Razão Sinal-Ruído
8.
Retina ; 32(7): 1337-42, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22481474

RESUMO

PURPOSE: To describe the outcomes of vitrectomy for optic disc pit-related maculopathy with central outer retinal dehiscence. METHODS: This prospective interventional case series included seven patients with optic disc pit with macular schisis and central outer retinal dehiscence who underwent vitrectomy with internal limiting membrane peeling, barrage laser photocoagulation, and gas tamponade and were followed for at least 6 months. The surgical outcomes in terms of restoration of macular anatomy and visual improvement were recorded at each visit by fundus photography and optical coherence tomography. RESULTS: The mean age of the patients was 21.3 ± 8.6 years (range, 10-35 years), and the mean duration of defective vision was 6.7 ± 8.5 months (range, 1-24 months). Preoperatively, the median best-corrected visual acuity (BCVA) was 20/60 (range, 20/40 to 20/120). Full-thickness macular holes were noticed in 4 patients 1 month postoperatively. Gas tamponade was repeated in two patients with large macular holes. By the final follow-up, macular holes had closed and BCVA improved in all patients except one. Final mean central macular thickness was 176.83 ± 55.74 µ, the range being 109 µ to 256 µ. The median postoperative BCVA was 20/30 (range, 20/20 to 20/80). Six of 7 patients (85.7%) had improvement in BCVA postoperatively (mean, +2 lines; range, 1-4 lines). Five patients (71%) achieved a postoperative BCVA of ≥20/30. Best-corrected visual acuity dropped by one line in the patient with persistent macular hole. CONCLUSION: Vitrectomy with internal limiting membrane peeling can achieve excellent final surgical outcomes in optic pit maculopathy with outer retinal dehiscence despite the potential for macular hole formation.


Assuntos
Anormalidades do Olho/cirurgia , Disco Óptico/anormalidades , Descolamento Retiniano/cirurgia , Retinosquise/cirurgia , Vitrectomia , Adolescente , Adulto , Membrana Basal/cirurgia , Criança , Tamponamento Interno , Anormalidades do Olho/complicações , Anormalidades do Olho/diagnóstico , Feminino , Fluorocarbonos/administração & dosagem , Humanos , Fotocoagulação a Laser , Masculino , Estudos Prospectivos , Descolamento Retiniano/complicações , Descolamento Retiniano/diagnóstico , Retinosquise/complicações , Retinosquise/diagnóstico , Hexafluoreto de Enxofre/administração & dosagem , Tomografia de Coerência Óptica , Resultado do Tratamento , Acuidade Visual/fisiologia , Adulto Jovem
9.
Parasit Vectors ; 15(1): 221, 2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35729601

RESUMO

BACKGROUND: ICMR-Vector Control Research Centre, Puducherry, India, developed two colonies of Aedes aegypti infected with wMel and wAlbB Wolbacia strains called Ae. aegypti (Pud) lines for dengue control. The sensitivity of wMel and wAlbB strains in Ae. aegypti (Pud) lines to heat stress was studied. METHODS: wMel and wAlbB infected and uninfected Ae. aegypti larvae (first to fourth instars) were reared in the laboratory to adults at 26 °C, 30 °C, 36 °C and 40 °C constant temperatures and also 26-30 °C, 26-36 °C and 26-40 °C diurnal cyclic temperatures. The adults were tested for Wolbachia infection. Experiments were also carried out rearing the larvae under simulated field conditions in summer (April and June) under sunlight using fully open and half open bowls and also under sunlight and natural shade. RESULTS: At 36 °C and 40 °C constant temperatures, complete larval mortality was observed. At 30 °C and 26 °C, no larval mortality occurred, but Wolbachia density was relatively low in wMel infected males compared to control (maintained at 26 ± 1 °C). At diurnal cyclic temperature of 26-40 °C, Wolbachia density was reduced in males of both the (Pud) lines, but not in females. At 26-36 °C, reduction in Wolbachia density was observed in wMel males but not in wAlbB males. At 26-30 °C, no significant reduction in Wolbachia density was observed with wMel and wAlbB strains. In simulated field conditions (April), under sunlight, the daytime water temperature reached a maximum of 35.7 °C in both full and half open bowls. No larval mortality occurred. Wolbachia frequency and density was reduced in wMel-infected Ae. aegypti (Pud) males from both type of bowls and in females from full open bowls, and in wAlbB males from half open bowls. In June, rearing of larvae under sunlight, the first-instar larvae experienced a maximum daytime water temperature of > 38 °C that caused complete mortality. No larval mortality was observed in bowls kept under shade (< 32 °C). CONCLUSIONS: Exposure of larvae to higher rearing temperatures in the laboratory and simulated-field conditions reduced the densities of wMel and wAlbB strains particularly in males, but the impact was more pronounced for wMel strain. The actual effect of heat stress on the stability of these two Wolbachia strains needs to be tested under natural field conditions.


Assuntos
Aedes , Wolbachia , Animais , Feminino , Resposta ao Choque Térmico , Larva , Masculino , Mosquitos Vetores , Água
10.
Front Microbiol ; 13: 947857, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35992676

RESUMO

Wolbachia, an intracellular maternally transmitted endosymbiont, has been shown to interfere with the replication of dengue virus in Aedes aegypti mosquitoes. The Wolbachia-transinfected Ae. aegypti has been currently released in many countries to test its effectiveness in preventing the transmission of dengue virus. ICMR-Vector Control Research Centre in collaboration with World Mosquito Program Monash University, Australia, has generated two new Wolbachia-introgressed Ae. aegypti Puducherry (Pud) lines via backcrossing Ae. aegypti females of Australian (Aus) strains, infected with wMel and wAlbB Wolbachia with wild-type Ae. aegypti Puducherry (Pud) males. Wolbachia infections are known to induce a fitness cost and confer benefit on the host mosquito populations that will influence spread of the Wolbachia into native wild mosquito populations during the field release. Hence, the induced fitness cost or benefit/advantage in the two newly generated Ae. aegypti (Pud) lines was assessed in the laboratory in comparison with the wild-type Ae. aegypti (Pud) strain. In addition, maternal transmission (MT) efficiency, induced cytoplasmic incompatibility (CI), and insecticide resistance status of the two (Pud) lines were determined to assess the likely frequency of wMel and wAlbB infections in the native wild population after field invasion. The study shows that wMel and wAlbB infections did not induce any fitness cost on the two newly generated (Pud) lines. Rather, in terms of wing length, fecundity, egg hatch rate, and adult survival, the Wolbachia introgression conferred fitness benefits on the (Pud) lines compared to uninfected Wolbachia free wild Ae. aegypti population. wMel and wAlbB exhibited a high maternal transmission (99-100%) and induced nearly complete (98-100%) cytoplasmic incompatibility. Both the (Pud) lines were resistant to deltamethrin, malathion, DDT, and temephos, and the level of resistance was almost the same between the two lines as in the wild type. Overall, the stable association of wMel and wAlbB established with Ae. aegypti and the reproductive advantages of the (Pud) lines encourage a pilot release in the field for population replacement potential.

11.
PLoS Negl Trop Dis ; 14(1): e0007862, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31978060

RESUMO

BACKGROUND: Lymphatic filariasis (LF) is targeted for elimination by the year 2020. As of 2017, 67 of the 72 endemic countries have implemented annual Mass Drug Administration (MDA) for interrupting LF transmission. Transmission Assessment Survey (TAS) is the recommended protocol to evaluate the impact of MDA and to decide when to stop MDA in an Evaluation Unit (EU, population ≤2 million). As the human infection levels go down with repeated MDA rounds, it becomes a challenge to select the appropriate survey methods to assess transmission interruption. This study validates a standard protocol for molecular xenomonitoring of infection in vectors (MX) at an EU as a complementary tool for TAS to stop MDA and its utility for post-MDA or post-validation surveillance. METHODOLOGY: The study was conducted in Cuddalore district, Tamil Nadu, India, which was found eligible for TAS after 15 annual rounds of MDA (4 with DEC alone and 11 with DEC plus albendazole). The district was divided into two EUs as per the TAS protocol and one EU was randomly selected for the study. A two-stage cluster design vector sampling, developed and validated at a sub-district level, was implemented in 30 randomly selected clusters in the EU. Female Culex quinquefasciatus were collected placing gravid traps overnight (1800-0600 hrs) inside the premises of systematically selected households. Pools of 20-25 blood-fed, semi-gravid and gravid Cx. quinquefasciatus were subjected to real-time quantitative PCR (polymerase chain reaction) assay for detecting Wuchereria bancrofti DNA. Pool infection rate (% of pools positive for W. bancrofti DNA), and the estimated prevalence of W. bancrofti DNA in mosquitoes and its 95% confidence interval were calculated. Additionally, in these 30 clusters, microfilaria (Mf) survey among individuals >5 years old was carried out. School-based TAS was conducted using Immunochromatographic Card Test (ICT) in the EU. Prepared itemized cost-menu for different cost components of MX survey and TAS were estimated and compared. RESULTS: MX survey showed that only 11 (3.1%) of the 358 pools (8850 Cx.quinquefasciatus females), collected from 30 clusters, were found positive for W. bancrofti DNA. The estimated vector infection rate was 0.13% (95% CI: 0.07-0.22%), below the provisional threshold (0.25%) for transmission interruption. Of 1578 children tested in the TAS, only four (0.25%) were positive for filarial antigenemia, and it is well below the critical cut-off (18 positives) for stopping MDA. Among 9804 persons tested in the 30 clusters, only four were found positive for Mf (0.04%; 95% CI: 0.01-0.1%). The Mf-prevalence was <1% threshold for transmission interruption in humans. The estimated costs for TAS and MX per EU were $14,104 USD and $14,259 USD respectively. CONCLUSIONS: The result of MX protocol was in good agreement with that of TAS, providing evidence to recommend MX as a complementary tool to TAS to decide on stopping MDA. MX can also be a potential surveillance tool for post-MDA and post-validation phases as it could detect sites with residual infection and risk of resurgence of transmission. MX is economically feasible as its cost is slightly higher than that of TAS.


Assuntos
Culex/parasitologia , DNA de Helmintos/análise , Filariose Linfática/prevenção & controle , Administração Massiva de Medicamentos , Wuchereria bancrofti/isolamento & purificação , Animais , Criança , Filariose Linfática/epidemiologia , Feminino , Humanos , Índia/epidemiologia , Mosquitos Vetores/parasitologia , Prevalência , Reação em Cadeia da Polimerase em Tempo Real , Wuchereria bancrofti/genética
12.
Res Rep Trop Med ; 10: 43-90, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31239804

RESUMO

Lymphatic filariasis (LF) is targeted for elimination by the year 2020. The Global Programme for Elimination of LF (GPELF) aims to achieve elimination by interrupting transmission through annual mass drug administration (MDA) of albendazole with ivermectin or diethylcarbamazine. The program has successfully eliminated the disease in 11 of the 72 endemic countries, putting in enormous efforts on systematic planning and implementation of the strategy. Mapping areas endemic for LF is a pre-requisite for implementing MDA, monitoring and evaluation are the components of programme implementation. This review was undertaken to assess how the mapping and impact monitoring activities have evolved to become more robust over the years and steered the LF elimination programme towards its goal. The findings showed that the WHO recommended mapping strategy aided 17 countries to delimit, plan and implement MDA in only those areas endemic for LF thereby saving resources. Availability of serological tools for detecting infection in humans (antigen/antibody assays) and molecular xenomonitoring (MX) in vectors greatly facilitated programme monitoring and evaluation in endemic countries. Results of this review are discussed on how these existing mapping and monitoring procedures can be used for re-mapping of unsurveyed and uncertain areas to ensure there is no resurgence during post-MDA surveillance. Further the appropriateness of the tests (Microfilaria (Mf)/antigenemia (Ag)/antibody(Ab) surveys in humans or MX of vectors for infection) used currently for post-MDA surveillance and their role in the development of a monitoring and evaluation strategy for the recently WHO recommended triple drug regimen in MDA for accelerated LF elimination are discussed.

13.
Cell Rep ; 25(11): 3123-3135.e6, 2018 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-30540944

RESUMO

Antibodies that bind residue K169 in the V2 region of the HIV-1 envelope correlated with reduced risk of infection in the RV144 vaccine trial but were restricted to two ED-motif-encoding light chain genes. Here, we identify an HIV-infected donor with high-titer V2 peptide-binding antibodies and isolate two antibody lineages (CAP228-16H/19F and CAP228-3D) that mediate potent antibody-dependent cell-mediated cytotoxicity (ADCC). Both lineages use the IGHV5-51 heavy chain germline gene, similar to the RV144 antibody CH58, but one lineage (CAP228-16H/19F) uses a light chain without the ED motif. A cocrystal structure of CAP228-16H bound to a V2 peptide identified a IGLV3-21 gene-encoded DDxD motif that is used to bind K169, with a mechanism that allows CAP228-16H to recognize more globally relevant V2 immunotypes. Overall, these data further our understanding of the development of cross-reactive, V2-binding, antiviral antibodies and effectively expand the human light chain repertoire able to respond to RV144-like immunogens.


Assuntos
Vacinas contra a AIDS/imunologia , Citotoxicidade Celular Dependente de Anticorpos/imunologia , Anticorpos Anti-HIV/imunologia , Proteína gp120 do Envelope de HIV/química , Infecções por HIV/imunologia , Infecções por HIV/virologia , Cadeias Leves de Imunoglobulina/metabolismo , Lisina/metabolismo , Alelos , Sequência de Aminoácidos , Anticorpos Anti-HIV/isolamento & purificação , Proteína gp120 do Envelope de HIV/metabolismo , Humanos , Cadeias Leves de Imunoglobulina/química , Modelos Moleculares , Peptídeos/metabolismo , Ligação Proteica , Doadores de Tecidos
15.
Pharmacogn Mag ; 10(Suppl 3): S639-44, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25298685

RESUMO

BACKGROUND: Cleistanthins A and B are isolated compounds from the leaves of Cleistanthus collinus Roxb (Euphorbiaceae). This plant is poisonous in nature which causes cardiovascular abnormalities such as hypotension, nonspecific ST-T changes and QTc prolongation. The biological activity predictions spectra of the compounds show the presence of antihypertensive, diuretic and antitumor activities. OBJECTIVE: Objective of the present study was to determine the in silico molecular interaction of cleistanthins A and B with Angiotensin I- Converting Enzyme (ACE-I) using Induced Fit Docking (IFD) protocols. MATERIALS AND METHODS: All the molecular modeling calculations like IFD docking, binding free energy calculation and ADME/Tox were carried out using Glide software (Schrödinger LLC 2009, USA) in CentOS EL-5 workstation. RESULTS: The IFD complexes showed favorable docking score, glide energy, glide emodel, hydrogen bond and hydrophobic interactions between the active site residues of ACE-I and the compounds. Binding free energy was calculated for the IFD complexes using Prime MM-GBSA method. The conformational changes induced by the inhibitor at the active site of ACE-I were observed based on changes of the back bone Cα atoms and side-chain chi (x) angles. The various physicochemical properties were calculated for these compounds. Both cleistanthins A and B showed better docking score, glide energy and glide emodel when compared to captopril inhibitor. CONCLUSION: These compounds have successively satisfied all the in silico parameters and seem to be potent inhibitors of ACE-I and potential candidates for hypertension.

16.
Protein J ; 32(8): 649-56, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24293155

RESUMO

Endo-1,4-Xylanase II is an enzyme which degrades the linear polysaccharide beta-1,4-xylan into xylose. This enzyme shows highest enzyme activity around 55 °C, even without being stabilized by the disulphide bridges. A set of nine high resolution crystal structures of Xylanase II (1.11-1.80 Å) from Trichoderma reesei were selected and analyzed in order to identify the invariant water molecules, ion pairs and water-mediated ionic interactions. The crystal structure (PDB-id: 2DFB) solved at highest resolution (1.11 Å) was chosen as the reference and the remaining structures were treated as mobile molecules. These structures were then superimposed with the reference molecule to observe the invariant water molecules using 3-dimensional structural superposition server. A total of 37 water molecules were identified to be invariant molecules in all the crystal structures, of which 26 invariant molecules have hydrogen bond interactions with the back bone of residues and 21 invariant water molecules have interactions with side chain residues. The structural and functional roles of these water molecules and ion pairs have been discussed. The results show that the invariant water molecules and ion pairs may be involved in maintaining the structural architecture, dynamics and function of the Endo-1,4-Xylanase II.


Assuntos
Endo-1,4-beta-Xilanases/metabolismo , Trichoderma/enzimologia , Domínio Catalítico , Cristalografia por Raios X , Endo-1,4-beta-Xilanases/química , Ligação de Hidrogênio , Íons/metabolismo , Modelos Moleculares , Estabilidade Proteica , Trichoderma/química
17.
Bioinformation ; 8(12): 568-73, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22829732

RESUMO

Protein Kinase C ß-II (PKC ß-II) is an important enzyme in the development of diabetic complications like cardiomyopathy, retinopathy, neuropathy, nephropathy and angiopathy. PKC ß-II is activated in vascular tissues during diabetic vascular abnormalities. Thus, PKC ß-II is considered as a potent drug target and the crystal structure of the kinase domain of PKC ß-II (PDB id: 2I0E) was used to design inhibitors using Structure-Based Drug Design (SBDD) approach. Sixty inhibitors structurally similar to Staurosporine were retrieved from PubChem Compound database and High Throughput Virtual screening (HTVs) was carried out with PKC ß-II. Based on the HTVs results and the nature of active site residues of PKC ß-II, Staurosporine inhibitors were designed using SBDD. Induced Fit Docking (IFD) studies were carried out between kinase domain of PKC ß-II and the designed inhibitors. These IFD complexes showed favorable docking score, glide energy, glide emodel and hydrogen bond and hydrophobic interactions with the active site of PKC ß-II. Binding free energy was calculated for IFD complexes using Prime MM-GBSA method. The conformational changes induced by the inhibitor at the active site of PKC ß-II were observed for the back bone Cα atoms and side-chain chi angles. PASS prediction tool was used to analyze the biological activities for the designed inhibitors. The various physicochemical properties were calculated for the compounds. One of the designed inhibitors successively satisfied all the in silico parameters among the others and seems to be a potent inhibitor against PKC ß-II.

18.
Indian J Pharmacol ; 44(2): 197-203, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22529475

RESUMO

OBJECTIVE: To investigate the involvement of alpha adrenergic receptors in hypotension induced by cleistanthin A and cleistanthin B. MATERIALS AND METHODS: Cleistanthins A and B were isolated from the leaves of Cleistanthus collinus using a column chromatographic method and purified. Structures were confirmed by spectroscopic analysis. The compounds were prepared for molecular docking studies using Ligprep 2.3 module and Induced Fit Docking was carried out against α-1 adrenergic receptors using Glide. The ex vivo experiments were carried out on male Wistar rats. Under anaesthesia, the femoral vein and carotid artery were cannulated for drug administration and for monitoring the blood pressure, respectively. The effect of epinephrine, norepinephrine, acetylcholine, histamine and dopamine were recorded before and after the administration of cleistanthin A or cleistanthin B. The molecular docking studies showed favorable molecular interactions, glide score, energy and emodel. RESULT: Cleistanthins A and B per se reduced the mean blood pressure and the effect was dose dependent. Both the compounds reduced the effect of epinephrine, norepinephrine and α-1 receptor activity of dopamine. Cleistanthin B significantly increased the duration of action of acetylcholine on mean blood pressure. CONCLUSION: The molecular docking and ex vivo studies conclude that cleistanthin A and cleistanthin B have significant α-1 adrenergic receptor antagonist effect on the peripheral vascular system.

19.
Bioinformation ; 7(3): 134-41, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22125384

RESUMO

Histone deacetylases (HDACs) are enzymes, which catalyze the removal of acetyl moiety from acetyl-lysine within the histone proteins and promote gene repression and silencing resulting in several types of cancer. HDACs are important therapeutic targets for the treatment of cancer and related diseases. Hydroxamic acid inhibitors show promising results in clinical trials against carcinogenesis. 120 hydroxamic acid derivatives were designed as inhibitors based on hydrophobic pocket and the Zn (II) catalytic site of HDAC8 active site using Structure Based Drug Design (SBDD) approach. High Throughput Virtual screening (HTVs) was used to filter the effective inhibitors. Induced Fit Docking (IFD) studies were carried out for the screening of eight inhibitors using Glide software. Hydrogen bond, hydrophobic interactions and octahedral coordination geometry with Zn (II) were observed in the IFD complexes. Prime MM-GBSA calculation was carried out for the binding free energy, to observe the stability of docked complexes. The Lipinski's rule of five was analyzed for ADME/Tox drug likeliness using Qikprop simulation. These inhibitors have good inhibitory properties as they have favorable docking score, energy, emodel, hydrogen bond and hydrophobic interactions, binding free energy and ADME/Tox. However, one compound (Cmp22) successively satisfied all the studies among the eight compounds screened and seems to be a promising potent inhibitor against HDAC8.

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